In recent years, fine inorganic particle-dispersed paste compositions in which fine inorganic particles of electroconductive particles, ceramics, glass, a phosphor or the like are dispersed in a binder resin have been used for obtaining sintered bodies of various shapes. For example, a paste composition in which fine metal particles are dispersed as electroconductive particles has been used in formation of circuits or the like on a substrate, a glass paste in which glass is dispersed or a phosphor paste in which phosphor is dispersed has been used in production of plasma display panels, a ceramic paste in which ceramics are dispersed has been molded into a green sheet, and then used in the production of a multilayer ceramic capacitor or the like.
Conventionally, as binder resins, ethyl cellulose, polyvinyl butyral, poly(methyl methacrylate) and the like have been used, and in these binder resins a degreasing temperature for removal by thermal decomposition is as high as 300° C. or higher in the production of a molded article, and the residual carbon is in a large amount, so that enormous energy is required in the production. Further, when fine inorganic particles unwantedly reacting with oxygen are handled, it is preferable that degreasing is carried out in a non-oxidative atmosphere, in which case a temperature required for degreasing would be at an even higher temperature. In view of the above, a binder resin capable of degreasing at a lower temperature even in a non-oxidative atmosphere, as in an oxidative atmosphere is desired.
In order to meet such demands, a polycarbonate resin produced from carbon dioxide and an epoxide has a low decomposition temperature of from 200° to 250° C. even in a non-oxidative atmosphere, and this polycarbonate resin has been studied to be used as a low-temperature decomposable binder. For example, Patent Publication 1 discloses a metal paste composition in which a polypropylene carbonate, which is one of aliphatic polycarbonates, is used as a binder, and similarly, Patent Publication 2 discloses a ceramic paste, and Patent Publication 3 discloses a glass paste.